Solid-state microsecond capacitance charger for high voltage and pulsed power

Abstract

A solid-state high-voltage pulse generator based on a three-phase chopper capacitance charger is described. In a first phase, an intermediate capacitor is resonance-charged via a diode. In a second phase, the intermediate capacitor is discharged to the load through one or more solid-state switches. In a third phase, the energy remaining in the intermediate capacitor is returned to a power-supply filter capacitor. In one embodiment, the three-phase chopper includes an intermediate capacitor that is charged by first and fourth branches of a bridge and discharged by second and third branches of a bridge. In one embodiment, each branch of the bridge includes a diode in series with an inductor. In one embodiment, a composite solid-state switch connects the intermediate capacitor to a primary winding of an output transformer such that the intermediate capacitor discharges through the primary winding. In one embodiment, a secondary winding of the output transformer is provided to an output load. In one embodiment, the output load is a reactive load. In one embodiment, the output load is a capacitive load.

1. A solid-state high-voltage pulse generator comprising:
 a reactive bridge having first, second, third, and fourth branches and first and second diagonals, each of said first, second, third, and fourth branches comprising a diode, said first diagonal comprising a power supply source of direct-current to provide direct-current to said first diagonal, said power supply having an output filter capacitor; 
 an intermediate capacitor provided across said second diagonal, said intermediate capacitor charged by said power supply through said first and third branches to a voltage substantially higher than a voltage of said power supply, said intermediate capacitor discharged to said filter capacitor by said second and fourth branches; 
 an output transformer having at least one primary winding and at least one secondary winding; 
 a series circuit comprising a solid-state switch in series with said primary winding, said series circuit provided in parallel with said intermediate capacitor; and 
 a control circuit to control said solid-state switch. 
 
     
     
       2. The solid-state high-voltage pulse generator of  claim 1 , wherein each of said first, second, third and fourth branches comprises a diode in series with an inductor. 
     
     
       3. A solid-state high-voltage pulse generator comprising:
 a reactive bridge having four branches wherein each branch comprises a diode; 
 a DC power supply having an output filter capacitor, said DC power supply providing DC current to a first diagonal of said bridge; 
 a first capacitor provided to a second diagonal of said branch, said first capacitor charged by current through first and fourth branches of said bridge to a voltage higher than a voltage of said power supply and discharged by current through second and third branches of said bridge; 
 a solid-state switch configured to provide said capacitor to a primary winding of an output transformer; and 
 a control circuit to control said solid-state switch. 
 
     
     
       4. The solid-state high-voltage pulse generator of  claim 3 , wherein said solid-state switch comprises a plurality of solid-state devices provided in parallel. 
     
     
       5. The solid-state high-voltage pulse generator of  claim 3 , wherein each branch of said bridge comprises a diode in series with an inductor. 
     
     
       6. The solid-state high-voltage pulse generator of  claim 3 , wherein said output transformer comprises multiple primary windings. 
     
     
       7. The solid-state high-voltage pulse generator of  claim 3 , wherein a secondary winding of said output transformer is provided to a capacitor. 
     
     
       8. The solid-state high-voltage pulse generator of  claim 3 , wherein a pulse shape of a pulse provided by a secondary winding of said output transformer is compressed by a compressor circuit. 
     
     
       9. The solid-state high-voltage pulse generator of  claim 3 , wherein said output transformer comprises a split-core transformer. 
     
     
       10. The solid-state high-voltage pulse generator of  claim 3 , wherein said output transformer comprises a Tesla transformer. 
     
     
       11. The solid-state high-voltage pulse generator of  claim 10 , wherein said output transformer comprises a Tesla transformer with at least a partial ferrite core. 
     
     
       12. A method for producing a high-voltage pulse, comprising:
 resonance charging a capacitor using direct current provided by a direct-current power supply through first and second legs of a reactive bridge such that a voltage across said capacitor is substantially hither than a voltage of said direct-current power supply; 
 closing a solid-state switch to connect a primary winding of an output transformer between said first and second legs; 
 discharging said capacitor to said primary winding; and 
 returning charge remaining in said capacitor to said power-supply through third and fourth legs of said bridge. 
 
     
     
       13. The method of  claim 12 , wherein said solid-state switch comprises a plurality of solid-state devices in parallel. 
     
     
       14. The method of  claim 12 , wherein each branch of said bridge comprises a diode in series with an inductor. 
     
     
       15. The method of  claim 12 , wherein said output transformer comprises multiple primary windings. 
     
     
       16. The method of  claim 12 , further comprising providing an output pulse from said output transformer to a capacitor. 
     
     
       17. The method of  claim 12 , further comprising compressing an output pulse of said output transformer. 
     
     
       18. The method of  claim 12 , wherein said output transformer comprises a split-core transformer. 
     
     
       19. The method of  claim 12 , wherein said output transformer comprises a Tesla transformer. 
     
     
       20. The method of  claim 12 , wherein said output transformer comprises a Tesla transformer with at least a partial ferrite core. 
     
     
       21. An apparatus for producing a high-voltage pulse, comprising:
 a full-wave reactive bridge comprising first, second, third, and fourth legs; 
 means for resonance charging a capacitor to a voltage higher than an input voltage using current from a direct-current power source, through said first and second legs; 
 means for partially discharging said capacitor to a primary winding of an output transformer; and 
 means for further discharging said capacitor through said third and fourth legs. 
 
     
     
       22. The apparatus of  claim 21 , further comprising means for compressing an output pulse of said output transformer. 
     
     
       23. A solid-state high-voltage pulse generator comprising:
 a full-wave bridge having first, second, third, and fourth branches, wherein each of said first, second, third, and fourth branches comprises a diode in series with a reactive element; 
 a direct current power supply provided to said full-wave bridge, said direct current power supply providing direct-current to said bridge; 
 a first capacitor provided between said first and fourth branches such that said capacitor is charged by said direct current through said first and fourth branches and discharged by current through said second and third branches to a voltage higher than a voltage of said direct current power supply; 
 a solid-state switch configured to connect a primary winding of an output transformer in parallel with said capacitor such that said capacitor discharges through said primary winding; and 
 a control circuit to control said solid-state switch. 
 
     
     
       24. The solid-state high-voltage pulse generator of  claim 23 , wherein said solid-state switch comprises a plurality of solid-state devices in parallel. 
     
     
       25. The solid-state high-voltage pulse generator of  claim 24 , wherein each branch of said bridge comprises a diode in series with an inductor. 
     
     
       26. The solid-state high-voltage pulse generator of  claim 24 , wherein said solid-state switch comprises one or more Insulated Gate Bipolar Transistors. 
     
     
       27. The solid-state high-voltage pulse generator of  claim 24 , wherein said solid-state switch comprises one or more MOSFETS. 
     
     
       28. The solid-state high-voltage pulse generator of  claim 24 , wherein said solid-state switch comprises one or more thyristors. 
     
     
       29. The solid-state high-voltage pulse generator of  claim 1 , wherein reactive elements in said first and third branches comprise sufficient inductive reactance to at least double the voltage provided from said power supply to said intermediate capacitor.